The duo from Montefiore Medical Center discussed a variety of topics surrounding an effort to improve seizure diagnosis and classification in newborns.
Recently, a Neonatal Seizures Task Force was established by the International League Against Epilepsy (ILAE) to develop a modification of the 2017 ILAE Classification of Seizures and Epilepsies, relevant to neonates. The new revisions published in February emphasize the use of electroencephalography (EEG) in the diagnosis of these seizures, as well as includes a classification of seizure types relevant to this age group.
The task force noted in their report that seizures are the most common neurological emergency in the neonatal period, occurring in 1-5 per 1000 live births and usually provoked by an acute illness or brain insult. ILAE past president Solomon, L. Moshe, MD, Charles Frost Chair in Neurosurgery and Neurology, and Elissa Yozawitz, MD, director of Neonatal Neurology, both at Montefiore Medical Center, were part of the task force.
As part of a new segment of NeuroVoices, Moshe and Yozawitz discussed the reasons behind the sudden change and the need to classify seizures in the neonate. They also detailed how the expanded use of technology played a major role in their conclusions.
Solomon Moshe, MD: Between 2009 and 2013, I was the president of the International League Against Epilepsy. In 2010, we published the first paper attempting a new classification of seizures. We mentioned there that the same mechanisms involved in the generation of adults are also in kids or babies. However, as we moved along, we realized that newborns represented a different group of patients because most of the seizures will appear as the patients is very sleepy, or even ‘comatose’ because they have suffered some degree of hypoxia ischemia, which is the most common cause of neonatal seizures.
I appointed 2 members of a new task force, which was Elissa Yozawitz, MD, and Ronit Pressler, MD, PhD, to see if we can address the classification of seizures in the neonate. This work was done over several years and was published just now. We started in 2012. Up to now, we continued reaching a consensus, which was reviewed by many people in the international league across the world. People agree that the proposal we have is a viable one, that can be useful in patients.
The main advantage we decided to use was the clinical semiology. How these seizures look together with EEG, and to classify different kinds of seizures. That’s because when you’re a baby, after hypoxia ischemia, you may make a lot of movements that are not necessarily a seizure and we don’t want to over treat that.
Elissa Yozawitz, MD: I just want to add that seizures in the newborn is very common. Sometimes the only way we know something is wrong with a baby is when it presents with a seizure. At this age, they’re mostly due to an acute injury. A lot of times, they might be electrographic, or they may have funny movements. We needed something based on only the neonates and also involved EEG, multiple centers, and took into account the baby. The baby can’t tell us how the baby is feeling. The baby doesn’t have generalized seizures like older people. That’s why we felt the neonate needed its own classification.
Elissa Yozawitz, MD: These babies are typically sick, so they do a lot of funny movements. Any movement they made; people would treat it. We made this classification start with first line EEG. We rule out right away, is this a seizure or not? Anything not a seizure is not included in the classification. Then we divided it into motor seizures and non-motor seizures. Motor seizures are a clonic or rhythmic jerking movement.
We also found that some of these clinical manifestations had certain ideologies associated with it. More specifically, clonic movements were often associated with stroke or structural etiologies. Other motor manifestations were epileptic spasms which is a quick body jerk. Myoclonic seizures is an irregular quick jerk that is different than clonic. Tonic seizures are when you see a prolonged stiffening. You need an EEG to see whether or not they’re seizures.
Then they’re the non-motor seizures where you definitely need the EEG because you can’t tell if the baby is having the seizure if they’re not connected. Autonomic seizures such as apneas are frequent in the neonate group, so we need to see if they’re seizures or not. Lastly is behavioral arrest, which is where the baby completely stops moving, which the only way to tell is if there’s an EEG associated with it. There’s a lot of different types of seizures than older groups.
Elissa Yozawitz, MD: Continuous EEG is the gold standard for diagnosing seizures. The prior classifications haven’t always used this as part of their classification system. This is beneficial because the ICU people and bedside nurses can see an abnormal movement if a baby is hooked up to an EEG and then press a button in real time. Since its automated, we can look at it anywhere and see whether or not it’s a seizure. In the past, the EEG was only done on paper. You had to be at the bedside, looking at the baby. It couldn’t be done all the time.
Since these are international guidelines, one of the critiques we got with our first draft was that not everyone had access to an EEG or ambulance. We came up with the Brighton Collaboration. We quoted them based on the diagnostic certainties of what’s a seizure and what’s not. Clonic seizures were found to be the most common to diagnose. If an expert looked at a clonic seizure, or even a vocal tonic seizure, they can say with probable certainty that it’s a seizure, whereas the other types of seizures you can’t tell for sure.
Solomon Moshe, MD: By understanding and linking it to the EEG, people will have a better visual representation of what the seizure types will be. The clinical observation and the widespread availability of video EEG has helped. In the future, we hope that even smaller, newer equipment will be developed that can easily be used in other countries that don’t have the EEG. Even in some countries, they use their phone to record the seizures. Assuming you get permission to take the movie, you can send it to a center, and they can tell you if they consider if it is a seizure or not.
Transcript edited for clarity.
To read the modifications, click here.